CHIANTI 10 includes updated atomic data for most of the ions along the beryllium, carbon and magnesium isoelectronic sequences. The helium-like ion models have been upgraded to two-ion models to enable modeling of recombination and autoionization processes. A new model of Fe VII has been added that produces many lines in the extreme ultraviolet part of the spectrum, and a number of energy levels of the coronal iron ions Fe X-XII have been updated.

IDL software has been added to allow the suppression of dielectronic recombination rates to be modeled, leading to ionization fraction tables that are density sensitive. Updated rates for Si-like ions recombining to P-like ions have been added, along with improved recombination rates into neutral helium.

A preprint of the paper describing CHIANTI 10 is available at arXiv.